1. Field of the Invention
Toxic agents can find a variety of uses. Particularly, where the cytotoxic agent is specific or can be modified to be specific for particular strains or cell types, the cytotoxic agent can find use in eliminating a particular strain or cell type from a culture or tissue involving a plurality of different types of cells. For example, in the case of malignancies, it is desirable to be able to specifically eliminate the malignant cells, without serious mortality to the normal or healthy cells.
One source of toxins is snake venom. A number of toxins are known. However, there is still interest in finding additional toxins so as to increase the armamentarium of toxins available for use in particular applications. Toxins may vary in the immune response to the toxin, ease of coupling to other reagents, site of action of the toxin, and the like. To discover a new toxin from snake venom requires an assay of utility, extensive extractions, purification, and analysis to establish purity and amino acid sequence.
2. Description of the Relevant Literature
Cytotoxic peptides isolated from the venom of several species of rattlesnake have been sequenced, isolated and described. Myotoxin is derived from the venom of the prairie rattlesnake, Crotalus (Fox et al., Biochemistry (1979) 18:678-83); Crotamine derived from the venom of the South American rattlesnake, Crotalus durissus terrificus (Lauree and Hoppe-Seyler, Physiol. Chem. (1975) 356:213-15); and toxic peptide C derived from the venom of the Southern Pacific rattlesnake, Crotalus viridis helleri (Maeda et al., Toxicon (1978) 16:431-41).